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The last avalanche forecast for the 2018/2019 season was posted on Sunday April 21st. Thank you to all who have supported the avalanche center through volunteer hours, field observations, and financial support.

Wind-loaded N-NE-E aspects and cross-loaded NW and SE aspects in near and above treeline terrain should hold the largest slabs of wind drifted snow. Some additional snow and wind today could cause these slabs to continue increasing in size and extent. Adding the weight of a person to these wind-loaded slopes could trigger a wind slabavalanche today. These avalanches may entrain enough snow to bury, injure, or kill a person. If the sun makes an appearance today, some of these wind slabs could be easier to trigger on sun-exposed slopes.

Maintain awareness of the conditions and terrain by using clues like cornices above a slope, blowing snow, drifted snow, and other wind created surface textures to locate potential wind slabs. This information will also help find softer non-wind-affected snow where recreation conditions may be more fun and less avalanche concerns exist.

Avalanche Problem 2: Storm Slab

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As the storm snow begins to settle and consolidate, storm slabavalanches should become more difficult to trigger in most places. However, human-triggered storm slabavalanches may remain possible today in some areas. Many of these soft slabs should remain small and only involve the new snow. Steep open slopes in sheltered terrain have the potential to hold lingering storm slabs. If the strong March sunshine breaks through the clouds today, some storm slabs may release more easily or loose wet snow instabilities may form on sun-exposed slopes.

Signs that storm snow weaknesses may remain active include shooting cracks and recent avalanche activity. Features of concern could include areas with convex rollovers, terrain traps, and areas of more complex terrain. Identifying these areas can help maintain an appropriate safety margin.

* Yesterday natural wind slab and storm slabavalanches occurred on Incline Lake Peak and on Tamarack Peak. The storm slabs failed on a layer of lower density snow about 8 to 12 inches below the surface. Some of the wind slabs had 1 to 2 ft crowns.

* Skier triggeredwind slabs of similar size also occurred on test slopes on Tamarack Peak and Andesite Peak.

Most remote sensors reported 9 to 11 inches of new snow in the last 24 hours with a few reporting 14 to 16 inches. Precipitation intensity peaked during the day yesterday. Snow levels and temperatures have been steadily falling since yesterday afternoon with snow levels now below 6000 ft. Temperatures should remain below normal. The forecast calls for more snow showers today with another few inches of accumulation. Some showers may linger into tomorrow evening. The gale force SW winds should decrease in strength today but still remain strong enough to transport snow in many areas.

Weather observations from along the Sierra Crest between 8200 ft. and 8800 ft.

80% probability of up to 3 inches. 20% probability 3 to 5 inches. | SWE = up to 0.20 inch.

40% probability up to 1 inch. 60% probability of no accumulation. | SWE = less than 0.10 inch.

Disclaimer

This avalanche forecast is provided through a partnership between the Tahoe National Forest and the Sierra Avalanche Center. This forecast covers the Central Sierra Nevada Mountains between Yuba Pass on the north and Ebbetts Pass on the south. Click here for a map of the forecast area. This forecast applies only to backcountry areas outside established ski area boundaries. This forecast describes general avalanche conditions and local variations always occur. This forecast expires 24 hours after the posted time unless otherwise noted. The information in this forecast is provided by the USDA Forest Service who is solely responsible for its content.

For a recorded version of the avalanche forecast call (530) 587-3558 x258

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This website is owned and maintained by the non-profit arm of the Sierra Avalanche Center. Some of the content is updated by the USDA avalanche forecasters including the forecasts and some observational data. The USDA is not responsible for any advertising, fund-raising events/information, or sponsorship information, or other content not related to the forecasts and the data pertaining to the forecasts.